Z56 Mr Forbes's Physical Notices of the Bay of Naples. 



of which we are so well acquainted with through their writ* 

 ings ; and if it did not then exist, what was its origin ? The 

 explanations which have been given may be reduced to two 

 classes ; that the Lake Agnano was nothing else anciently than 

 the fish-pond of Lucullus, or that it was formed by a volcanic 

 subsidence in the middle ages. The former opinion is not with- 

 out plausibility, and is strongly upheld by Eustace. * Clu- 

 verius seems also disposed to it. It is universally believed 

 that Lucullus had a villa on this spot, and ruins are shown on 

 the banks of the Lake, which may very probably have form- 

 ed part of it. We are told by Pliny that the ponds cost 

 more than the villa itself, which gives us a surprising idea of 

 their magnitude ; and we are likewise told that there was a 

 communication between them and the sea. An artificial cut 

 through a portion of the hills which bound the Lake I have 

 certainly observed, and considered it in this view ; but as 

 things stand at present, it seems unlikely that a low enough 

 level can exist for that purpose, but it is by no means impos- 

 sible, and would be worth a trial. I had intended to have 

 made one, but the accident which occurred to the barometer 

 which I destined for the measurement of Vesuvius disap- 

 pointed me. Others with Breislak suppose that the Lake of 

 Agnano owes its existence to volcanic action in the middle 

 ages ; and, as the former opinion derives most weight from his- 

 torical evidence, so does the present one from its physical con- 

 stitution, and I am disposed to think that the latter testimony 

 predominates. All writers seem to agree, that the hollow in 

 which the Lake of Agnano is situated displays the features of 

 a true, though much degraded, volcanic crater, and forms one 

 of a class of objects quite peculiar, of which we have undoubt- 

 ed examples in Lake Avernus, and the Lakes of Albano and 

 Nemi. I have ascertained, too, by examination, that there is 

 neither introduction or emission of water by streams in the 

 example before us, which is a frequent character of volcanic 

 lakes, and furnishes a presumption that Lucullus could not 

 have employed as a fish-pond a basin in which there is no free 

 current, and which sometimes approaches to stagnation, for 



• Italy J iii. 430- Legliorn Edit. 



